Patent EP-B1-1705009 describes an automatic handling and transport device for printing sleeves which enables performing printing sleeve changing operations in a flexographic printer while the flexographic printer is operating, said device comprising a sleeve holding support that can be positioned in alignment with a sleeve-bearing shaft and in proximity with same and a securing tool configured for being moved by moving means between a transfer position, in which said securing tool interacts with said sleeve installed on said sleeve-bearing shaft to hold it or release it by one end, and a transport position in which the sleeve secured by the securing tool is left arranged on said holding support of the device. The device for automatic handling is installed in a basic mobile unit prepared for moving the device in a first direction (X) and in a second direction (Y), transverse to said first direction (X) and parallel to said sleeve-bearing shaft to provide said alignment positions.
The device explained in said background document can present alignment problems if sleeves of considerable weight are to be handled, as is the case of the sleeves of an offset printing machine, and in any case the operation of transferring the sleeves from the sleeve-bearing shaft of the machine to the holding support of the device is a critical aspect of the operating cycle, in that machine shaft misalignments with respect to an initial or theoretical position of said holding support and positioning inaccuracies can result in the sleeve being jammed during transfer to or from the described holding support, which must be kept perfectly co-aligned at all times with said sleeve-bearing shaft of the machine.
Patent EP-B2-1776231 describes a system for the replacement of sleeves of a printing machine where there has been provided a basic mobile unit, consisting of a known programmable robotic manipulator with two rotational joints, and pushing means arranged both in the printing machine and in a holding support of said robotic manipulator in order to transfer said sleeves to and from said holding support by pushing means. To transfer printing sleeves, the printer is equipped with pushing devices, and the robotic manipulator lacks means for the extraction of the sleeves itself by means of pulling on them, this operation depending on the pushing devices of the printer.
With regard to transferring the sleeves from the shafts of the printing machine to the support of the manipulator and vice versa, this second background document has the same problems derived from the weight of the sleeves and misalignments between shaft and support mentioned above, in addition to requiring pushing means arranged in the printer, making it difficult to implement or preventing the implementation of this sleeve changing system in already existing printers.
The invention object of the present patent application proposes an automatic device that is intended for facilitating the transfer of printing sleeves of any class, span and weight to or from a sleeve-bearing shaft of the machine and to or from a holding support arranged in co-alignment with said shaft, almost completely eliminating the possibility of said jams as a result of a self-alignment system, also being suitable for moving and arranging said sleeves in a storage area.